#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int main(){
	char arr1[]={0};
	char arr2[]="Hello world";
	strcpy(arr1,arr2);
	printf("%s\n",arr1);
	memset(arr2,'W',5);
	printf("%s\n",arr2);
	return 0;
}
